Officer Matthews received a more detailed report from the police accident
investigator: The 1978 Ford was 30 feet into the intersection, coming
to a stop close to the northeast corner of S. College and Delaware Avenue.
The 1988 Chevrolet van was found directly behind the car. Both vehicles
showed skid marks from the south side of the intersection to the position
where they came to a stop. Our analysis showed that the Ford left an 80-foot
skid mark prior to being struck by the van, while the van left a 20-foot
skid mark prior to impact.

A drag sled was used to determine that the average deceleration on the
road was 19 ft/s2. The speed limit on S. College is 25 mph. The van weighs
approximately twice the weight of the car, and since the car was stopped
just prior to impact, speed of the van prior to impact was approximately
1.5 times the speed of the two vehicles just after impact.

Questions:

Sketch the intersection, position of the car and van, and appropriate
skid marks.

Using what you know about reaction time, and stopping distance, how
far from the intersection was Sandy when she first saw the students
and yellow light?

Explain the sequence of events from the time Sandy first noticed the
yellow light to the time when both vehicles came to a stop in the intersection.

Should either driver be charged with speeding? Justify your answer
with data.

Was Jerry following too closely behind Sandy? Do we have data to help
answer that question?

Should Sandy or Jerry be charged in the accident? Justify your reasoning.